Coinbase CEO Brian Armstrong said x402 "is going to be huge eventually," arguing that AI agents will need built-in payment rails as they increasingly buy tools, data, and digital services on their own. He said those agents will eventually far outnumber humans, making automated transactions a core part of how AI systems operate online. x402 is an open payments protocol built around HTTP 402, "Payment Required," and is designed to let AI agents pay automatically for API access or other digital services. The system mainly supports stablecoin-based onchain payments, meaning agents can pay immediately when they need a service rather than relying on separate accounts or subscription setups.